Abstract |
The Little Patuxent River (basin code 02131105) located in Anne Arundel and Howard Counties, was identified in Marylands Integrated Report as impaired by cadmium (Cd), sediments, nutrients (1996 listings), and impacts to biological communities (2002) (MDE 2008). Centennial Lake located within the watershed was identified as impaired by phosphorus and sediments (1998 listings). Except for Centennial Lake, all impairments are listed for non-tidal streams. The 1996 nutrient listing was refined in the 2008 Integrated Report and phosphorus was identified as the specific impairing substance. Similarly, the 1996 sediments listing was refined in the 2008 Integrated Report to a listing for total suspended solids. A 2008 WQA addressing the Cd impairment is pending USEPA approval and will remove the Little Patuxent watershed from Category 5 for Cd impairment to Category 2. Phosphorus and sediment TMDLs for Centennial Lake were approved in 2001. In 2002, the State began listing biological impairments on the Integrated Report. The current Maryland Department of Environment (MDE) biological assessment methodology assesses and lists only at the Maryland 8-digit watershed scale, which maintains consistency with how other listings on the Integrated Report are made, how TMDLs are developed, and how implementation is targeted. |